Electro-osmosis in a saturated porous rigid medium is studied by both theoretical and experimental approach. Relationships giving liquid and electrical coupled macroscopic flows are obtained from the homogeneization m...
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Electro-osmosis in a saturated porous rigid medium is studied by both theoretical and experimental approach. Relationships giving liquid and electrical coupled macroscopic flows are obtained from the homogeneization method. They point out possible non symmetrical cross effects that explain deviations from Onsager reciprocal relations. Experiments on a kaolinite are reported which exhibit an important non symmetrical coupling.
A sensitive method for the quantitation of IgG on platelets had not been demonstrated until 1975, when Dixon, Rosse, and Ebbert described a quantitative antiglobulin consumption test useful in detecting platelet assoc...
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A sensitive method for the quantitation of IgG on platelets had not been demonstrated until 1975, when Dixon, Rosse, and Ebbert described a quantitative antiglobulin consumption test useful in detecting platelet associated IgG (N Engl J Med 292:230, 1975). A modification of that technique has rendered the assay reproducible and removed the need for daily repetition of a standard IgG titration curve for quantitation. This modification utilizes 1-ethyl-3-3(dimethylaminopropyl)carbodiimide HCl (ECDI) (Sigma, E-7750), in place of chromic chloride, as a coupling agent for attaching IgG (Miles 64-145) to sheep cells (SRC), used as indicator cells. The ECDI consistently couples IgG to SRC and does not subject the SRC to sporadic spontaneous lysis, as does chromic chloride. This modification permits the detection of IgG on platelets (Direct Test), or in sera (Indirect Test) by incubation of a washed platelet pool with sera in vitro, and testing as in the Direct Test. Normal values of 0.01-1.56 and 0.14-1.6 femtograms (f) per platelet have been obtained for the Direct and Indirect Tests, respectively. In six cases of suspected ITP, values ranged 12.0-221.0 f and 2.9-37.6 ffor the Direct and Indirect Tests, respectively. In conclusion, in disease states or other abnormal situations, quantities of IgG can be detected that are not usually present on the platelets of normal subjects.
The effect of alteration of redox potential on the kinetics offluorescence induction in pea chloroplasts was investigated. Potentiometric titration of the initial (fi) level offluorescence recorded upon shutter open...
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The effect of alteration of redox potential on the kinetics offluorescence induction in pea chloroplasts was investigated. Potentiometric titration of the initial (fi) level offluorescence recorded upon shutter opening gave a 2 component curve, with Em(7) at -20 mV and -275 mV, almost identical to results obtained using continuous low intensity illumination (Horton, P. et al.). The slow or tail phase of induction observed in the presence of DCMU [3-(3'',4''-dichlorophenyl)-1,1-dimethylurea] can be eliminated by poising the redox potential at .apprx. 0 to +50 mV. At this potential fi was increased by less than 10% and the higher potential quencher described above was only marginally reduced. The disappearance of the slow phase titrated as an n = 1 component with an Em(7) of +120 mV. It seems unlikely that the slow phase offluorescence induction is due to photoreduction of the -20 mV quencher. Current ideas concerning heterogeneity on the acceptor side of photosystem II were discussed.
Two non-reducing hexasaccharides isolated from the roots of Asparagus officinalis were identified as 1 f -β-fructofuranosyl-6 G (1-β-fructofuranosyl) 3 sucrose and 1 f (1-β-fructofuranosyl) 2 -6 G (1-β-fructofuran...
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Two non-reducing hexasaccharides isolated from the roots of Asparagus officinalis were identified as 1 f -β-fructofuranosyl-6 G (1-β-fructofuranosyl) 3 sucrose and 1 f (1-β-fructofuranosyl) 2 -6 G (1-β-fructofuranosyl) 2 sucrose by examination of the constituent saccharides, GLC analysis of methyl derivatives, and investigation of partial acid hydrolysates and β-fructofuranosidase-catalysed hydrolysis products.
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